Image generation device and image projection apparatus

ABSTRACT

An image generation device includes an image generator, a stationary unit, a movable unit, a driver, and a wiring board. The image generator receives light and generate an image. The movable unit includes a movable plate movably supported by the stationary plate of the stationary unit, the image generator mounted on the movable plate, and a diffusion heat radiator connected to the movable plate, to cool the image generator. The driver relatively moves the movable unit with respect to the stationary unit. The driver includes a driving coil disposed in the radiator and a driving magnet opposed to the coil. The wiring board is connected to the movable unit, to pass a current through at least the coil. A movable area of the wiring board in which the wiring board moves with movement of the movable unit does not overlap any of the coil and the magnet in plan view.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is based on and claims priority pursuant to 35U.S.C. § 119(a) to Japanese Patent Application No. 2016-236841, filed onDec. 6, 2016, in the Japan Patent Office, the entire disclosure of whichis hereby incorporated by reference herein.

BACKGROUND Technical Field

Aspects of the present disclosure relate to an image generation deviceand an image projection apparatus.

Related Art

For example, there is known an image projection apparatus in which adisplay element as an image generator generates a projection image basedon input image data, and the generated projection image is magnified andprojected on a screen or the like.

For example, an image projection apparatus is proposed that performspixel shift by shifting the optical axis with a pixel shifter withrespect to light beams emitted from a plurality of pixels of an imagegenerator, to project an image having a higher resolution than theresolution of a display element.

SUMMARY

In an aspect of the present disclosure, there is provided an imagegeneration device that includes an image generator, a stationary unit, amovable unit, a driver, and a wiring board. The image generator receiveslight and generate an image. The stationary unit includes a stationaryplate. The movable unit includes a movable plate and a diffusion heatradiator. The movable plate is movably supported by the stationaryplate. The image generator is mounted on the movable plate. Thediffusion heat radiator is connected to the movable plate, to cool theimage generator. The driver relatively moves the movable unit withrespect to the stationary unit. The driver includes a driving coil and adriving magnet. The driving coil is disposed in the diffusion heatradiator. The driving magnet is opposed to the driving coil. The wiringboard is connected to the movable unit, to pass a current through atleast the driving coil. A movable area of the wiring board in which thewiring board moves with movement of the movable unit does not overlapwith any of the driving coil and the driving magnet in plan view.

In another aspect of the present disclosure, there is provided an imageprojection apparatus that includes a light source, the image generationdevice, an illumination optical unit, and a projection optical unit. Theimage generation device receives light from the light source andgenerate an image. The illumination optical unit guides the light fromthe light source to the image generation device. The projection opticalunit projects the image generated by the image generation device.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The aforementioned and other aspects, features, and advantages of thepresent disclosure would be better understood by reference to thefollowing detailed description when considered in connection with theaccompanying drawings, wherein:

FIG. 1 is a diagram of an example of an image projection apparatusaccording to an embodiment of the present disclosure;

FIG. 2 is a block diagram of a configuration of a projector according toan embodiment of the present disclosure;

FIG. 3 is a perspective view of an optical engine according to anembodiment of the present disclosure;

FIG. 4 is a schematic view of an internal configuration of an opticalengine according to an embodiment of the present disclosure;

FIG. 5 is a schematic view of an internal configuration of the opticalengine according to an embodiment of the present disclosure;

FIG. 6 is a perspective view of an image generation unit;

FIG. 7 is an exploded perspective view of the image generation unit ofFIG. 6;

FIG. 8 is an exploded perspective view of the image generation unit ofFIG. 6;

FIG. 9 is a plan view of the image generation unit viewed from a topplate side;

FIG. 10 is a cross-sectional view of the image generation unit cut alongline A-A in FIG. 9;

FIG. 11 is a partially enlarged view of a region indicated by RS of FIG.10;

FIG. 12 is an illustration of an arrangement relationship betweendriving magnets and driving coils.

FIG. 13 is an exploded perspective view of a configuration of a movableunit;

FIG. 14 is an illustration of a movable area of a driving FPC;

FIG. 15 is an illustration of an arrangement relationship between adriving coil, a driving magnet, and the driving FPC; and

FIG. 16 is a side view of the driving coil, the driving magnet, and thedriving FPC seen from a direction indicated by arrows E of FIG. 15.

The accompanying drawings are intended to depict embodiments of thepresent disclosure and should not be interpreted to limit the scopethereof. The accompanying drawings are not to be considered as drawn toscale unless explicitly noted.

DETAILED DESCRIPTION

In describing embodiments illustrated in the drawings, specificterminology is employed for the sake of clarity. However, the disclosureof this patent specification is not intended to be limited to thespecific terminology so selected and it is to be understood that eachspecific element includes all technical equivalents that operate in asimilar manner and achieve similar results.

Although the embodiments are described with technical limitations withreference to the attached drawings, such description is not intended tolimit the scope of the disclosure and all of the components or elementsdescribed in the embodiments of this disclosure are not necessarilyindispensable.

Hereinafter, embodiments of the present disclosure are described withreference to attached drawings. Note that embodiments are not limited tothe embodiments described below, but can be appropriately modifiedwithout departing from the gist of the present invention. In thefollowing description, a side (top-plate side) of an image projectionapparatus closer to a top plate is referred to as “upper” or “above”,and a side (heat-sink side) of the image projection apparatus closer toa heat sink may be referred to as “lower” or “below”.

<Image Projection Apparatus>

An image projection apparatus according to an embodiment of the presentdisclosure is described below. In the present embodiment, a case inwhich the image projection apparatus is a projector is described.

FIG. 1 is an illustration of an example of the image projectionapparatus according to an embodiment of the present disclosure. Asillustrated in FIG. 1, a projector 1 as the image projection apparatusaccording to the present embodiment includes an exit window 2, anexternal interface (external I/F) 3, and an optical engine to generate aprojection image. For example, when image data is transmitted from apersonal computer or a digital camera connected to the external I/F 3,the projector 1 generates a projection image based on the image datatransmitted by the optical engine and projects an image P from the exitwindow 2 onto a screen S.

In the following drawings, the term “X1-X2 direction” represents thewidth direction of the projector 1, the term “Y1-Y2 direction”represents the depth direction of the projector 1, and the terms “Z1-Z2direction” represents the height direction of the projector 1. In thefollowing description, in the Z1-Z2 direction, a side (exit-window side)of the projector 1 closer to the exit window 2 may be referred as“upper” and the opposite side of the exit-window side may be referred toas “lower”.

FIG. 2 is a block diagram of a configuration of the projector 1according to an embodiment of the present disclosure. As illustrated inFIG. 2, the projector 1 includes the external I/F 3, a power supply 4, amain switch (SW) 5, an operation unit 6, a system control unit 10, a fan20, and an optical engine 25.

The power supply 4 is connected to a commercial power supply, convertsthe voltage and frequency for an internal circuit of the projector 1,and supplies power to, e.g., the system control unit 10, the fan 20, theoptical engine 25.

The main switch (SW) 5 is used for ON/OFF operation of the projector 1by the user. When the main switch (SW) 5 is turned on while the powersupply 4 is connected to the commercial power supply via, e.g., a powercord, the power supply 4 starts supplying power to parts of theprojector 1. When the main switch (SW) 5 is turned off, the power supply4 stops supplying power to parts of the projector 1.

The operation unit 6 includes, e.g., keys to accept various operationsby the user, and is disposed, for example, on an upper surface of theprojector 1. The operation unit 6 accepts operations by the user, suchas adjustment of the size, color tone, and focus of the projectionimage. The user's operation accepted by the operation unit 6 is sent tothe system control unit 10.

The external I/F 3 includes a connection terminal connected to, forexample, a personal computer and a digital camera, and outputs imagedata transmitted from the connected device to the system control unit10.

The system control unit 10 includes an image controller 11 and a drivecontroller 12. The system control unit 10 includes, for example, acentral processing unit (CPU), a read only memory (ROM), and a randomaccess memory (RAM). The function of each part of the system controlunit 10 is realized, for example, by the CPU executing a program storedin the ROM in cooperation with the RAM.

Based on the image data input from the external I/F 3, the imagecontroller 11 controls a digital micro mirror device (DMD) 551, which isan image generator disposed in an image generation unit 50 as an imagegeneration device of the optical engine 25, to generate an image to beprojected on the screen S.

The drive controller 12 controls a drive unit to move a movable unit 55that is movably disposed in the image generation unit 50, and controlsthe position of the DMD 551 disposed in the movable unit 55.

The fan 20 is rotated under the control of the system control unit 10,to cool a light source 30 that is a lamp unit of the optical engine 25.

The optical engine 25 includes the light source 30, an illuminationoptical unit 40 as an image display device, the image generation unit 50as the image generation device, and a projection optical unit 60, andprojects an image onto the screen S under control of the system controlunit 10.

The light source 30 is, for example, a mercury high pressure lamp, axenon lamp, or a light emitting diode (LED) and is controlled by thesystem control unit 10 to irradiate the illumination optical unit 40with light.

The illumination optical unit 40 includes, for example, a color wheel, alight tunnel, and a relay lens, and guides the light emitted from thelight source 30 to the DMD 551 disposed in the image generation unit 50.

The image generation unit 50 includes a stationary unit 51 that is astationary portion securely supported, and the movable unit 55 that is amovable part movably supported by the stationary unit 51. The movableunit 55 includes the DMD 551. The position of the movable unit 55 withrespect to the stationary unit 51 is controlled by the drive controller12 of the system control unit 10. The DMD 551 is an example of the imagegeneration unit. The DMD 551 is controlled by the image controller 11 ofthe system control unit 10 and modulates the light guided by theillumination optical unit 40 to generate a projection image.

The projection optical unit 60 includes, for example, a plurality ofprojection lenses and mirrors and enlarges an image generated by the DMD551 of the image generation unit 50 to project the image on the screenS.

<Optical Engine>

Next, configurations of parts of the optical engine 25 are furtherdescribed below. FIG. 3 is a perspective view of the optical engine 25in an embodiment of the present disclosure. As illustrated in FIG. 3,the optical engine 25 is disposed inside the projector 1, and includesthe light source 30, the illumination optical unit 40, the imagegeneration unit 50, and the projection optical unit 60.

The light source 30 is disposed on a side surface of the illuminationoptical unit 40 and irradiates light in an X2 direction. Theillumination optical unit 40 guides the light irradiated from the lightsource 30 to the image generation unit 50 disposed below theillumination optical unit 40. The image generation unit 50 generates aprojection image using the light guided by the illumination optical unit40. The projection optical unit 60 is disposed above the illuminationoptical unit 40 and projects the projection image generated by the imagegeneration unit 50 to the outside of the projector 1.

The optical engine 25 according to the present embodiment is configuredto project an image upward by using the light emitted from the lightsource 30. In some embodiments, the optical engine 25 may be configuredto project an image in the horizontal direction.

FIGS. 4 and 5 are schematic views of an internal configuration of theoptical engine 25.

As illustrated in FIG. 4, the illumination optical unit 40 includes acolor wheel 401, a plane mirror 405, and a concave mirror 406.

The color wheel 401 is, for example, a disk with filters of respectivecolors of, for example, R (red), G (green), and B (blue) in differentportions in the circumferential direction. By rotating the color wheel401 at high speed, the color wheel 401 time-divides the light emittedfrom the light source 30 into RGB colors. The plane mirror 405 and theconcave mirror 406 reflect the light time-divided into RGB colors by thecolor wheel 401 to the DMD 551 provided in the image generation unit 50.A base 403 supports, for example, the color wheel 401, the plane mirror405, and the concave mirror 406. The base 403 is fixed inside a housingof the projector 1.

In the illumination optical unit 40, for example, a light tunnel and arelay lens may be provided between the color wheel 401 and the planemirror 405.

The image generation unit 50 includes the DMD 551. The DMD 551 modulatesthe reflected light from the concave mirror 406 to generate a projectionimage. The projection image generated by the DMD 551 is guided to theprojection optical unit 60 through the illumination optical unit 40. Aspecific configuration of the image generation unit 50 is describedlater.

As illustrated in FIG. 5, in the projection optical unit 60, aprojection lens 601, a return mirror 602, and a curved mirror 603 areprovided inside a case.

The projection lens 601 includes a plurality of lenses, and focuses theprojection image generated by the DMD 551 of the image generation unit50 on the return mirror 602. The return mirror 602 and the curved mirror603 reflect the focused projection image so as to enlarge the focusedprojection image, and project the focused projection image onto, e.g.,the screen S outside the projector 1.

Image Generation Unit Next, the image generation unit 50 according tothe present embodiment is further described. FIG. 6 is a perspectiveview of the image generation unit 50. FIGS. 7 and 8 are explodedperspective views of the image generation unit 50.

As shown in FIGS. 6 to 8, the image generation unit 50 includes thestationary unit 51, the movable unit 55, a driver 56, and a detector 57.Next, a description is given of a configuration of each of thestationary unit 51, the movable unit 55, the driver 56, and the detector57.

Stationary Unit

The stationary unit 51 includes a top plate 511 as a first stationaryplate, an intermediate plate 512 as a second stationary plate, a baseplate 513 as a third stationary plate, a control board 514, a sub plate515 as a fourth stationary plate, and a DMD mask 516 as a cover member.In the stationary unit 51, the top plate 511 is fixedly supported on alower surface of the base 403 (see FIG. 4) of the illumination opticalunit 40 (see FIG. 4).

The top plate 511, the intermediate plate 512, the base plate 513, andthe sub plate 515 are flat plate members.

The top plate 511 and the intermediate plate 512 have a center hole 511a and a center hole 512 a, respectively, at positions corresponding tothe DMD 551 of the movable unit 55. The base plate 513, the controlboard 514, and the sub plate 515 have a central groove 513 a, a centralgroove 514 a, and a central groove 515 a, respectively, through whichthe heat transfer portion 573 of the heat sink 554 is inserted, atportions facing the DMD 551 provided on the DMD substrate 552.

The intermediate plate 512 is disposed on the lower surface (the surfaceon the base plate 513 side) of the top plate 511 and is fixed to thelower surface of the base plate 513. The intermediate plate 512 isformed so as to surround the periphery of the DMD 551, and has thecenter hole 512 a in the portion corresponding to the DMD 551. Theintermediate plate 512 disposed in the gap between the top plate 511 andthe movable plate 553 reduces the gap between the top plate 511 and themovable plate 553. Such a configuration can reduce dust entering throughthe gap between the top plate 511 and the movable plate 553 and adheringto the DMD 551 without hampering the mobility of the movable plate 553.Thus, degradation of the quality of the projection image due to dust orother substance is suppressed. Further, since the intermediate plate 512holds support balls 522 on a side closer to the top plate 511 (the topplate 511 side) in the through hole 521, the intermediate plate 512functions to regulate movement positions of the support balls 522 on theside closer to the top plate 511.

The base plate 513 is disposed with a predetermined gap on the lowerside (the base plate 513 side) of the intermediate plate 512 and issecured by a plurality of supports 518.

The control board 514 is disposed on the lower surface (the surface onthe heat sink 554 side) of the base plate 513 and is fixed by screws.The control board 514 receives the position information output from theHall elements 558 via a position detection flexible printed circuitboard (position detecting FPC) 564 disposed on the upper surface of theDMD substrate 552. According to the received position information, thecontrol board 514 controls the amount of current to be passed throughthe driving coils 533 a, 533 b, 533 c, and 533 d (hereinafter, may besimply referred to as “driving coil 533”) via a driving flexible printedboard (driving FPC) 575 as a wiring board disposed on the upper surface(the surface on the top plate 511 side) of the heat sink 554, to controlthe movable unit 55.

The sub plate 515 is disposed on the lower surface of the base plate 513via the control board 514 with a predetermined gap.

The DMD mask 516 is disposed on the upper surface of the top plate 511around the center hole 511 a and fixed to the top plate 511 by screws534.

The top plate 511, the base plate 513, and the sub plate 515 aredisposed in parallel to each other via predetermined gaps by theplurality of supports 518. An upper end portion of the support 518 ispress-fitted into a support hole 511 b of the top plate 511, and a lowerend portion of the support 518, at which a male thread is formed, isinserted into a support hole 513 b of the base plate 513. Then, thesupport 518 is fixed in support holes 515 b of the sub plate 515 byscrews 520. The support 518 forms a certain gap between any two of thetop plate 511, the base plate 513, and the sub plate 515 and supportsthe top plate 511, the base plate 513, the sub plate 515 in parallel.Accordingly, the top plate 511 is disposed in parallel with the baseplate 513 via a predetermined gap.

From the viewpoint of the driving performance of the image generationunit 50, the position detecting magnets 531 and the driving magnets 532a, 532 b, 532 c, and 532 d (hereinafter may be simply referred to as“driving magnets 532”) are heavy, the position detecting magnets 531 andthe driving magnets 532 are arranged on the stationary unit 51 side.However, from the viewpoint of the magnetic circuit, the members onwhich the position detecting magnets 531 and the driving magnets 532 aredisposed are preferably magnetic bodies. Accordingly, each of the topplate 511 and the sub plate 515, on which the position detecting magnets531 and the driving magnets 532 are disposed, is formed of a magneticmaterial, such as iron or ferritic stainless steel.

In addition, the intermediate plate 512 and the base plate 513 may bemade of any of a magnetic material and a non-magnetic material. In thepresent embodiment, the base plate 513 is also preferably made of amagnetic material, such as iron or ferritic stainless steel, forexample, so that a magnetic flux from the driving magnets 532 does notleak from the sub plate 515 and adversely affect the Hall elements 558.Since the base plate 513 is made of a magnetic material, the magneticfields generated by the position detecting magnets 531 can be separatedby the base plate 513 from the magnetic fields generated by the drivingmagnets 532.

The top plate 511 and the base plate 513 support the movable plate 553between the top plate 511 and the base plate 513 at three supportingpositions so as to be movable in a direction parallel to the plane ofthe movable plate 553. The support structure of the movable plate 553 isfurther described.

FIG. 9 is a plan view of the image generation unit 50 viewed from thetop plate 511 side. FIG. 10 is a cross-sectional view of the imagegeneration unit 50 cut along line A-A in FIG. 9. FIG. 11 is a partiallyenlarged view of a region indicated by RS of FIG. 10. As illustrated inFIGS. 9 to 11, the intermediate plate 512 has three through holes 521that pass through the intermediate plate 512 in the vertical direction.A recess is formed by the lower surface of the top plate 511 and thethrough hole 521 of the intermediate plate 512. The support ball 522 isinserted into the through hole 521, and the through hole 521 rotatablyholds the support ball 522.

The base plate 513 has three support holes 523 through the base plate513 in the vertical direction. The three support holes 523 are disposedin the base plate 513 so as to correspond to the three through holes521, respectively, of the top plate 511. In the support hole 523 of thebase plate 513, a cylindrical holding member 524 having a female threadon the lower inner circumferential surface thereof is inserted from thetop plate 511 side and is seated on the base plate 513. A positionadjustment screw 525 has a male thread on an outer periphery thereof.The position adjustment screw 525 is inserted into the holding member524 via a spring 526 from a side opposite to the top plate 511, andscrewed at a lower end of the holding member 524. As a result, thesupport ball 522 is rotatably held in a space formed by the holdingmember 524 and the position adjustment screw 525.

Each support ball is rotatably held by the top plate 511 and the holdingmember 524 of the base plate 513, and at least a portion of the supportball 522 projects beyond the through hole 521 and the holding member524. Accordingly, each support ball 522 contacts the movable plate 553disposed between the top plate 511 and the base plate 513.

The three through holes 521 of the top plate 511 and the three holdingmembers 524 of the base plate 513 are disposed so that three pairs ofsupport balls 522 are disposed between the top plate 511 and the baseplate 513. Accordingly, the three pairs of support balls 522 pinch andsupport the movable plate 553 between the top plate 511 and the baseplate 513 at three positions of the movable plate 553. The movable plate553 is supported from both sides of the movable plate 553 by the supportballs 522 so as to be movable in a direction parallel to the top plate511 and the base plate 513 and parallel to the surface of the movableplate 553. The support balls 522 also pinch the movable plate 553 in astate of point contact with the movable plate 553 from both sides of themovable plate 553. Such a configuration can reduce friction of themovable plate 553 with the support balls 522 when the movable plate 553moves.

The amount of projection of the support ball 522, which is disposed inthe holding member 524, from an upper end of the holding member 524varies as the position of the position adjustment screw 525 displaces inthe Z1 direction or the Z2 direction. Accordingly, the distance betweenthe base plate 513 and the movable plate 553 can be appropriatelyadjusted by changing the amount of projection of the support ball 522using the position adjustment screw 525.

Note that the number and positions of the supports 518 disposed in thestationary unit 51 are not limited to the configuration exemplified inthe present embodiment.

Further, the base plate 513 includes through holes 529 through whichscrews 528 to fix the top plate 511 to the illumination optical unit 40(see FIGS. 2 to 5) are inserted.

As illustrated in FIGS. 6 to 8, the position detecting magnets 531 aredisposed on the upper surface (the surface on the top plate 511 side) ofthe movable plate 553. Each of the position detecting magnets 531 ismade of a rectangular parallelepiped permanent magnet and forms amagnetic field extending to the DMD substrate 552 disposed between thetop plate 511 and the base plate 513.

Further, the driving magnets 532 are disposed on the lower surface (thesurface on the heat sink 554 side) of the sub plate 515. The drivingmagnets 532 are disposed at four positions so as to surround the centralgroove 513 a of the base plate 513 and the central groove 515 a of thesub plate 515. Each of the driving magnets 532 is disposed so as to facethe driving coils 533 disposed on the upper surface of the heat sink554. The driving magnets 532 are two pairs of two rectangularparallelepiped magnets arranged so that the longitudinal directions ofthe two rectangular parallelepiped magnets are parallel to each other.Each of the driving magnets 532 forms a magnetic field extending to theheat sink 554. The driving magnets 532 and the driving coils 533generates a drive force to move the movable plate 553.

Movable Unit

As illustrated in FIGS. 6 to 8, the movable unit 55 includes the DMD551, the DMD substrate 552 as a first movable plate, the movable plate553 as a second movable plate, and the heat sink 554 as a diffusion heatradiator. The movable unit 55 is movably supported by the stationaryunit 51.

The DMD 551 is disposed on the upper surface (the surface opposite tothe top plate 511) of the DMD substrate 552. The DMD 551 is exposed tothe upper surface side of the movable plate 553 through the center hole511 a of the top plate 511. The DMD 551 is connected to the DMDsubstrate 552 via a socket 556. The outer periphery of the DMD 551 iscovered by a cover 557. The DMD 551 has an image generation surface inwhich a plurality of movable micromirrors are arranged in a latticepattern. Each micromirror of the DMD 551 is disposed so that a mirrorsurface can tilt around a torsion axis. The driving of each micromirrorof the DMD 551 is turned ON/OFF based on an image signal transmittedfrom the image controller 11 (see FIG. 1) of the system control unit 10(see FIG. 1).

For example, when the micromirror is “ON”, the inclination angle of themicromirror is controlled so as to reflect the light from the lightsource 30 (see FIGS. 2 to 4) to the projection optical unit 60 (seeFIGS. 2 to 4). On the other hand, for example, when the micromirror is“OFF”, the inclination angle of the micromirror is controlled in such adirection as to reflect the light from the light source 30 (see FIGS. 2to 4) toward a OFF light plate.

As described above, the DMD 551 controls the inclination angle of eachmicromirror according to the image signal transmitted from the imagecontroller 11 (see FIG. 2). The light irradiated from the light source30 (see FIGS. 2 to 4) and passing through the illumination optical unit40 (see FIGS. 2 to 4) is modulated to generate a projection image.

The DMD substrate 552 is disposed between the top plate 511 and the baseplate 513 of the stationary unit 51, and is connected to the lowersurface of the movable plate 553. The DMD substrate 552 displacestogether with the movable plate 553.

The DMD 551 is disposed on the upper surface of the DMD substrate 552.The DMD 551 is connected to the DMD substrate 552 via the socket 556.The outer periphery of the DMD 551 is covered by the cover 557.

In the DMD substrate 552, cutouts are formed on the periphery of the DMDsubstrate 552 so as not to contact the connection posts 572 of the heatsink 554 so that the movable plate 553 is fixed by the connection posts572 of the heat sink 554.

For example, when the movable plate 553 and the DMD substrate 552 arejointly fastened to the heat sink 554 by the connection post 572, theDMD substrate 552 might deform, thus causing the image generationsurface of the DMD 551 to be inclined with respect to the movementdirection and distort an image. Hence, the cutouts are formed in theperipheral of the DMD substrate 552 so that the connection posts 572 ofthe heat sink 554 are connected to the movable plate 553 while avoidingthe DMD substrate 552. Accordingly, the heat sink 554 is connected tothe movable plate 553, thus reducing the possibility of occurrence ofdeformation due to receiving the load from the heat sink 554 on the DMDsubstrate 552. Therefore, the image generation surface of the DMD 551 iskept to be parallel to the movement direction, thus allowing the imagequality to be maintained.

The cutouts of the DMD substrate 552 are formed so as not to contact theholding member 524 of the base plate 513 so that the support balls 522held by the base plate 513 contact the movable plate 553 while avoidingthe DMD substrate 552. Thus, contacting of the DMD substrate 552 withthe support balls 522 can suppress the occurrence of, e.g., deformationin the DMD substrate 552. Accordingly, the image generation surface ofthe DMD 551 can be kept to be parallel to the movement direction, thusmaintaining the image quality.

Note that, instead of the cutouts, for example, through holes may beformed in the DMD substrate 552 as long as the through holes are shapedso as to prevent the DMD substrate 552 from contacting the connectionposts 572 of the heat sink 554 and the support balls 522.

In addition, the position detecting FPC 564 is disposed on the uppersurface (the surface on the top plate 511 side) of the DMD substrate552. On the upper surface of the position detecting FPC 564, the Hallelements 558 as magnetic sensors are disposed at positions opposed tothe position detecting magnets 531 disposed on the upper surface of themovable plate 553. The position of the DMD 551 is detected by the Hallelements 558 and the position detecting magnets 531 disposed on the baseplate 513.

Note that, in the image generation unit 50 according to the presentembodiment, from the viewpoint of driving performance, components withsmall weight are arranged in the movable unit 55 and components withlarge weight are arranged in the stationary unit 51. Accordingly, theposition detecting magnets 531 and the driving magnets 532 may beincluded in the stationary unit 51. In addition to the Hall elements 558and the driving coils 533, the position detecting FPC 564 and thedriving FPC 575 electrically connected to the Hall elements 558 and thedriving coils 533 may also be included in the movable unit 55.

The movable plate 553 is disposed between the top plate 511 and the baseplate 513 of the stationary unit 51 and is supported by the three pairsof support balls 522 so as to be movable in the direction parallel tothe surface of the movable plate 553 as described above.

The movable plate 553 is formed of a flat plate member, and a centerhole 553 a is formed at a position corresponding to the DMD 551 disposedon the DMD substrate 552. Through holes 559, through which screws to fixthe top plate 511 to the illumination optical unit 40 are inserted, areformed in the movable plate 553.

The movable plate 553 is connected and fixed with an adhesive in a statein which the interval between the movable plate 553 and the DMD 551 areadjusted with screws inserted into the connection holes so that thesurface of the movable plate 553 and the image generation surface of theDMD 551 are parallel to each other.

The movable plate 553 has connection holes 560 at positionscorresponding to the connection posts 572 of the heat sink 554. Themovable plate 553 is fixed to the upper ends of the connection posts 572together with the DMD substrate 552 by screws 561 inserted into theconnection holes 560.

When the movable plate 553 moves parallel to the surface, the DMDsubstrate 552 connected to the movable plate 553, the heat sink 554, andthe DMD 551 disposed on the DMD substrate 552 also move together withthe movable plate 553. Accordingly, when the surface of the movableplate 553 is not parallel to the image generation surface of the DMD551, the image generation surface of the DMD 551 might be inclined withrespect to the movement direction, thus causing a distorted image. Inthe present embodiment, the interval between the movable plate 553 andthe DMD substrate 552 is adjusted and the surface of the movable plate553 and the image generation surface of the DMD 551 are kept parallel toeach other. Such a configuration can suppress deterioration in imagequality.

Note that the movable plate 553 is supported by the pair of supportballs 522 in this embodiment, but embodiments of the present disclosureare not limited to the configuration of the present embodiment. Forexample, the DMD substrate 552 may be supported by the pair of supportballs 522.

In the present embodiment, the pair of support balls 522 are disposed inthe through hole 521 and the holding member 524. However, theconfiguration of supporting the DMD substrate is not limited to theconfiguration of the present embodiment. Instead of the through hole 521and the holding member 524, for example, a pair of convex portions maybe disposed facing the top plate 511 and the movable plate 553,respectively.

In addition, the movable plate 553 has a movable-range restriction hole562 a and a movable-range restriction groove 562 b at positionscorresponding to the supports 518 of the stationary unit 51. The movableplate 553 might be greatly displaced due to, for example, vibration orsome abnormality in a state in which the supports 518 of the stationaryunit 51 are disposed in the movable-range restriction hole 562 a and themovable-range restriction groove 562 b. In such a case, the movablerange of the movable plate 553 is restricted by the movable plate 553contacting the supports 518.

Note that, for example, the number, position, and shape of each of themovable-range restriction hole 562 a and the movable-range restrictiongroove 562 b are not limited to the configurations exemplified in thepresent embodiment. For example, the number of each of the movable-rangerestriction hole 562 a and the movable-range restriction groove 562 bmay be one or plural. Further, the shape of each of the movable-rangerestriction hole 562 a and the movable-range restriction groove 562 bmay be different from the shape of the present embodiment and may be,for example, rectangle or circular. In addition, the movable plate 553and the DMD substrate 552 may be connected to each other with aconfiguration different from the configuration of the presentembodiment.

The position detecting magnets 531 are disposed at plural positions onthe upper surface (surface on the top plate 511 side) of the movableplate 553. Each of the position detecting magnets 531 is made of arectangular parallelepiped permanent magnet and forms a magnetic fieldextending to the DMD substrate 552 disposed between the top plate 511and the base plate 513.

The heat sink 554 includes heat radiating portions 571, the connectionposts 572, and the heat transfer portion 573.

The heat radiating portion 571 has a plurality of fins in a lowerportion thereof, and dissipates the heat generated in the DMD 551. Firstrecesses 574A to accommodate the driving coils 533 and a second recess574B to accommodate the driving FPC 575 are disposed on the uppersurface of the heat radiating portion 571 (see FIG. 12). A third recess574C to accommodate wires 576 connecting the driving coils 533 to thedriving FPC 575 is further disposed on the upper surface of the heatradiating portion 571 (see FIG. 12). Grooves 577 through which the wires576 pass are formed between the first recesses 574A and the secondrecess 574B.

The first recesses 574A are formed at positions facing the drivingmagnets 532 disposed on the lower surface of the base plate 513. Thedriving coils 533 face the driving magnets 532 disposed on the lowersurface of the base plate 513.

The second recess 574B is disposed at an inner side of a base body ofthe heat sink 554 than the first recesses 574A in plan view. In thepresent embodiment, since the four, first recesses 574A are arranged ina U shape, the second recess 574B is disposed inside a region surroundedby the first recesses 574A. Note that the term “plan view” used hereinmeans a view from the normal direction of the upper surface of the imagegeneration unit 50.

The connection posts 572 are disposed at three positions on theperiphery of the upper surface of the heat sink 554 so as to extend inthe Z1 direction from the upper surfaces of the heat radiating portions571. The movable plate 553 is coupled and fixed to the upper ends of theconnection posts 572 by screws 561 inserted into the connection holes560 of the movable plate 553. The connection posts 572 are connected tothe movable plate 553 by the cutouts of the DMD substrate 552 withoutcontacting the DMD substrate 552.

The heat transfer portion 573 is at a position opposed to the DMD 551and is a columnar member extending from the upper surface of the heatradiating portion 571 in the Z1 direction. The heat transfer portion 573of the heat sink 554 is inserted into the central grooves 513 a, 514 a,and 515 a of the base plate 513, the control board 514, and the subplate 515, and contacts the bottom surface of the DMD 551. The heattransfer portion 573 of the heat sink 554 contacts the bottom surface ofthe DMD 551 to transfer the heat generated in the DMD 551 to the heatradiating portion 571 and radiate heat, thus cooling the DMD 551.Suppressing the temperature rise of the DMD 551 by the heat sink 554 canreduce occurrence of troubles, such as malfunctions or failures due tothe temperature rise of the DMD 551.

To enhance the cooling effect of the DMD 551, for example, anelastically deformable heat transfer sheet may be disposed between theupper surface of the heat transfer portion 573 and the DMD 551, forexample, between the heat transfer portion 573 of the heat sink 554 andthe DMD 551. The heat transfer sheet improves the thermal conductivitybetween the heat radiating portion 571 of the heat sink 554 and the DMD551 and improves the cooling effect of the DMD 551.

Further, in the present embodiment, it can be said that four pillarsstand on the heat sink 554. One pillar is the heat transfer portion 573.The heat transfer portion 573 is located at the center of the heat sink554, is a pillar to contact the DMD 551, and has a function oftransferring the heat of the DMD 551 to the fins. The remaining threepillars are connection posts 572.

The heat sink 554 is disposed to move together with the movable plate553 and the DMD substrate 552. Since the heat transfer portion 573 isconstantly in contact with the DMD 551, the heat sink 554 can constantlyradiate the heat generated in the DMD 551 and efficiently cool the DMD551.

The driving FPC 575 is disposed on the upper surface (the surface on thetop plate 511 side) of the heat sink 554. The driving FPC 575 iselectrically connected to the driving coils 533.

In the present embodiment, in the image generation unit 50, the driveforce for moving the movable unit 55 is generated by the top plate 511,the base plate 513, the sub plate 515, the movable plate 553, and thedriving FPC 575.

Through holes 579 of the top plate 511, the through holes 559 of themovable plate 553, and the through holes 529 of the base plate 513 areformed so as to face each other in the Z1-Z2 direction. The screws tofix the top plate 511 to the illumination optical unit 40 are insertedinto the through holes 579 of the top plate 511, the through holes 559of the movable plate 553, and the through holes 529 of the base plate513.

A space corresponding to the thickness of the socket 556 and the DMD 551is generated between the surface of the DMD substrate 552 and the imagegeneration surface of the DMD 551. Accordingly, for example, if the DMDsubstrate 552 is disposed above the top plate 511, the space from thesurface of the DMD substrate 552 to the image generation surface of theDMD 551 would be a dead space, and the device configuration might becomelarge.

In the present embodiment, the DMD substrate 552 is disposed between thetop plate 511 and the base plate 513, and the top plate 511 is disposedin the space from the surface of the DMD substrate 552 to the imagegeneration surface of the DMD 551. Accordingly, since the space from thesurface of the DMD substrate 552 to the image generation surface of theDMD 551 can be effectively utilized, the height of the image generationunit 50 in the Z1-Z2 direction can be reduced and the image generationunit 50 can be downsized. Therefore, the image generation unit 50 can beassembled not only to a large-sized projector but also to a small-sizedprojector, thus enhancing versatility.

At least one or more of the top plate 511, the DMD substrate 552, themovable plate 553, and the holding member 524 is preferably formed of aconductive material such as stainless steel, aluminum, magnesium alloy,or the like. Thus, for example, electrical noise generated in the DMD551 and the DMD substrate 552 is released to, for example, the housingof the illumination optical unit 40 through the top plate 511 and theDMD substrate 552. Such a configuration can reduce noise leakage to theoutside.

Driver

As illustrated in FIG. 8, the driver 56 includes the driving magnets 532disposed on the sub plate 515, the driving coils 533 disposed on theheat sink 554, and the driving FPC 575. The driving magnets 532 and thedriving coils 533 are disposed so as to be opposed to each other betweenthe sub plate 515 and the heat sink 554.

As illustrated in FIG. 12, the driving magnets 532 are disposed in fourpoints in a U shape along the shape of the sub plate 515. In the presentembodiment, the driving magnets 532 b and 532 c are two permanentmagnets whose longitudinal direction is parallel to the X1-X2 direction.In addition, the driving magnets 532 a and 532 d are two permanentmagnets whose longitudinal direction is parallel to the Y1-Y2 direction.Each of the driving magnets 532 forms a magnetic field extending to theheat sink 554.

Each of the driving coils 533 is formed by winding an electric wirearound an axis parallel to the Z1-Z2 direction and is mounted to thefirst recess 574A formed on the upper surface of the heat radiatingportion 571 of the heat sink 554.

The driving coil 533 is fixed in the first recess 574A so as topartially have a gap between the driving coil 533 and the first recess574A. For example, an adhesive is used to fix the driving coil 533. Aresin material having a low thermal conductivity is used as theadhesive. Fixing the driving coil 533 in the first recess 574A with theadhesive can reduce the transfer of the heat generated in the drivingcoil 533 to the heat sink 554. Note that the adhesive to be used is notparticularly limited to any specific adhesive, and any suitable adhesivecan be used as long as the adhesive has a low thermal conductivity andcan fix the driving coil 533 in the first recess 574A. For example, apart of the bottom surface or the side surface of the first recess 574Ais preferably applied with the adhesive, and the other surface of thefirst recess 574A is preferably a gap. When an air layer is partiallypresent between the driving coil 533 and the first recess 574A, the airlayer can further reduce the transfer of the heat generated in thedriving coil 533 to the heat sink 554.

The driving magnets 532 of the sub plate 515 and the driving coils 533of the heat sink 554 are arranged so as to face each other in a state inwhich the movable unit 55 is supported by the stationary unit 51. When acurrent is supplied to the driving coil 533, a Lorentz force serving asa drive force to move the movable unit 55 is generated in the drivingcoil 533 by the magnetic fields formed by the driving magnets 532.

When the Lorentz force is transmitted to the heat sink 554, the movableplate 553 also displaces according to the displacement of the heat sink554 since the heat sink 554 is connected to the movable plate 553.Accordingly, the movable unit 55 receives the Lorentz force generatedbetween the driving magnets 532 and the driving coils 533 and isdisplaced linearly or rotationally in the X-Y plane with respect to thestationary unit 51.

In the present embodiment, the driving coil 533 a and the driving magnet532 a, the driving coil 533 d and the driving magnet 532 d are disposedso as to be opposed to each other in the X1-X2 direction. When a currentis passed through the driving coil 533 a and the driving coil 533 d, aLorentz force in the Y1 direction or the Y2 direction is generated. Themovable plate 553 moves in the Y1 direction or the Y2 direction by theLorentz force generated in the driving coil 533 a and the driving magnet532 a and the Lorentz force generated in the driving coil 533 d and thedriving magnet 532 d.

In addition, in the present embodiment, the driving coil 533 b and thedriving magnet 532 b are arranged side by side in the Y1-Y2 direction,and the driving coil 533 c and the driving magnet 532 c are arrangedside by side in the Y1-Y2 direction. The driving magnet 532 b and thedriving magnet 532 c are arranged such that the longitudinal directionsof the driving magnet 532 b and the driving magnet 532 c areperpendicular to the longitudinal directions of the driving magnet 532 aand the driving magnet 532 d, respectively. In such a configuration,when current is passed through the driving coil 533 b and the drivingcoil 533 c, a Lorentz force in the X1 direction or X2 direction isgenerated as illustrated in FIG. 15.

The movable plate 553 moves in the X1 direction or the X2 direction dueto the Lorentz force generated in the driving coil 533 b and the drivingmagnet 532 b and the Lorentz force generated in driving coil 533 c andthe driving magnet 532 c. The movable plate 553 is displaced so as torotate in the XY plane by the Lorentz forces generated in the oppositedirections between the pair of the driving coil 533 b and the drivingmagnet 532 b and the pair of the driving coil 533 c and the drivingmagnet 532 c.

For example, a Lorentz force in the X1 direction is generated in thedriving coil 533 b and the driving magnet 532 b, and a current flows sothat a Lorentz force in the X2 direction is generated in the drivingcoil 533 c and the driving magnet 532 c. In such a case, the movableplate 553 is displaced so as to rotate clockwise in plan view. A Lorentzforce in the X2 direction is generated in the driving coil 533 b and thedriving magnet 532 b, and a current flows so that a Lorentz force in theX1 direction is generated in the driving coil 533 c and the drivingmagnet 532 c. In such a case, the movable plate 553 is displaced so asto rotate counterclockwise in plan view.

In this manner, the image generation unit 50 can relatively move themovable unit 55 with respect to the stationary unit 51, and can freelyshift the DMD 551 in the X direction and the Y direction and move in therotation direction. Accordingly, for example, the image generation unit50 can move the DMD 551 in the oblique 45 degree direction by a halfpixel pitch of a certain frequency and output an image matching thedirection, thereby achieving high resolution. Further, since the DMD 551can be freely shifted in the X direction and in the Y direction andmoved in the rotation direction, the projection image can be easilyshifted in the horizontal direction and the vertical direction andeasily adjusted in the rotation direction.

The magnitude and direction of the current flowing through each drivingcoil 533 are controlled by the drive controller 12 of the system controlunit 10. The drive controller 12 controls, for example, the movement(rotation) direction, the movement amount, and the rotation angle of themovable plate 553 according to the magnitude and direction of thecurrent flowing to each driving coil 533.

As illustrated in FIG. 12, the driving FPC 575 is disposed in the secondrecess 574B on the upper surface (the surface on the top plate 511 side)of the heat sink 554. The driving FPC 575 is, for example, a wiringboard including a metal layer made of, e.g., copper having high thermalconductivity. The driving FPC 575 is electrically connected to thedriving coil 533 by the wires 576.

Since the driving FPC 575 is connected to the control board 514 via aconnector, one end of the driving FPC 575 is moved in parallel in theplane or rotated by the movable unit 55 and the other end is secured tothe stationary unit 51. Accordingly, the driving FPC 575 need to have afunction of absorbing the movement amount of the stationary unit 51without hampering the movement of the stationary unit 51. Therefore, aplurality of creases are formed in the driving FPC 575 so as to absorbthe movement amount of the stationary unit 51 even when one side of thedriving FPC 575 moves with the other end of the driving FPC 575 fixed.

Next, an arrangement relationship between the driving magnets 532, thedriving coils 533, and the driving FPC 575 is further described below.

FIG. 13 is an exploded perspective view of a configuration of themovable unit. FIG. 14 is an illustration of a movable area of thedriving FPC. FIG. 15 is an illustration of the arrangement relationshipof the driving coils, the driving magnets, and the driving FPC. FIG. 16is an illustration of the driving coils, the driving magnets, and thedriving FPC seen from a direction indicated by arrows E in FIG. 15. Asillustrated in FIGS. 13 to 16, the driving coil 533 and the drivingmagnet 532 are opposed to each other in substantially the same positionin plan view.

When the movable unit 55 is in a stationary state, a predetermined gapis disposed between the driving FPC 575, the driving coil 533, and thedriving magnet 532 in plan view. In plan view, the driving FPC 575 isdisposed at a position not overlapping any of the driving coil 533 andthe driving magnet 532.

The driving FPC 575 is disposed in the second recess 574B of the heatsink 554. Accordingly, when the movable unit 55 is in a driven state,the movable plate 553 and the driving FPC 575 also move as the heat sink554 moves. In the present embodiment, in plan view, a movable area a ofthe driving FPC 575 caused by the movement of the heat sink 554 is aregion not overlapping with any of the driving coils 533 and the drivingmagnets 532. That is, the driving FPC 575 is disposed at a position atwhich the driving FPC 575 does not overlap with any of the driving coils533 and the driving magnets 532 in plan view even when the movable unit55 is driven.

With such a configuration, the distance between the driving magnet 532and the driving coil 533 can be made shorter by an amount that thedriving FPC 575 is not disposed between the driving magnet 532 and thedriving coil 533. Therefore, the above-described arrangement of thedriving FPC 575 can increase the magnetic flux density of the magneticfield generated by the driving magnet 532, as compared with the case inwhich the driving FPC 575 is disposed between the driving magnet 532 andthe driving coil 533. Accordingly, the driving performance of themovable unit 55 can be enhanced.

Even if a solder rises above the driving FPC 575 when the wire 576 ofthe driving coil 533 is soldered to the driving FPC 575, such aconfiguration can suppress the contact of raised solder with the drivingmagnets 532 on the lower surface of the sub plate 515. Accordingly, thedriving performance of the movable unit 55 can be stably maintainedwithout being reduced.

That is, since the wire 576 of the driving coil 533 is connected to thedriving FPC 575 by solder, the solder attached to the driving FPC 575might rise. When the heat sink 554 moves, the solder raised on thedriving FPC 575 might contact the driving magnets 532 on the lowersurface of the sub plate 515, thus causing sliding friction. In such acase, the driving performance of the movable unit 55 might be reduced,or the driving coil 533 might be short-circuited, thus stopping themovable unit 55. In the present embodiment, to reduce the occurrence ofsuch a failure, the driving FPC 575 and the driving coil 533 arearranged as close as possible to each other while stably maintaining thedriving performance of the movable unit 55.

The driving coils 533 are disposed in the first recesses 574A and thedriving FPC 575 is disposed in the second recess 574B. In plan view, themovable area a of the driving FPC 575 does not overlap with the drivingcoils 533. Further, the driving coil 533 is fixed with the adhesive in astate in which a gap is present partially in the first recess 574A. Thatis, the heat of the driving coil 533 is transmitted to the heat sink 554side via the adhesive having a low thermal conductivity and the airlayer. Such a configuration can reduce the transfer of the heatgenerated by the driving coil 533 to the heat sink 554, thus suppressingthe driving FPC 575 from being heated by the heat generated by thedriving coil 533.

The driving FPC 575 is a wiring board including a metal layer and havingheat conductivity. Accordingly, if the heat generated by the drivingcoil 533 is transmitted to the driving FPC 575, the heat might betransferred to the heat sink 554. At this time, since heat from the DMD551 is also transferred to the heat sink 554, a heat quantity greaterthan the quantity of heat to be dissipated might be transferred to theheat sink 554. As a result, the heat transferred from the driving FPC575 to the heat sink 554 is transferred to the DMD 551 or the heatradiating portion 571, which might heat the DMD 551 to be originallycooled. In the present embodiment, the transfer of the heat generated bythe driving coil 533 to the driving FPC 575 can be suppressed, thuspreventing or reducing the warming of the DMD 551.

Further, even if the solder attached on the driving FPC 575 rises, theabove-described configuration can suppress the contact of the raisedsolder with the driving magnet 532. Therefore, when the wire 576 of thedriving coil 533 is connected to the driving FPC 575, the load of work,such as adjustment of the amount of solder, can be reduced, thusenhancing the productivity of the image generation unit 50.

As described above, in the image generation unit 50 according to thepresent embodiment, the movable area a of the driving FPC 575 does notoverlap with any of the driving coils 533 and the driving magnets 532 inplan view. Such a configuration can reduce the contact of theabove-described raised solder with the driving magnet 532 whileshortening the distance between the driving magnet 532 and the drivingcoil 533. Such a configuration can also reduce the transfer of the heatgenerated by the driving coil 533 to the driving FPC 575 and theinfluence of the transferred heat on the cooling effect of the DMD 551.Thus, according to the present embodiment, the DMD 551 can be stablycooled while more stably maintaining a high degree of drivingperformance.

The movable area a of the driving FPC 575 is determined based on, e.g.,the arrangement position and the size of the driving FPC 575 so that thedriving FPC 575 does not overlap with the driving magnets 532 in planview, irrespective of which direction, e.g., the movable plate 553 andthe heat sink 554 included in the movable unit 55 move.

The driving coils 533 are disposed in the first recesses 574A, and thedriving FPC 575 is disposed in the second recess 574B. In the presentembodiment, the upper surface of the driving coil 533 (the surface onthe driving magnet 532 side) and the upper surface of the driving FPC575 (an end surface on the driving magnet 532 side) are arranged on thesame plane. Such arrangement of the driving coil 533 and the driving FPC575 allows the wires 576 of the driving coils 533 to be connected to thedriving FPC 575 through the grooves 577 connecting the first recesses574A to the second recess 574B. Accordingly, the wires 576 of thedriving coils 533 do not extend in the vertical direction, thussuppressing the application of unnecessary load to the wires 576 whenthe wires 576 of the drive coils 533 are connected to the driving FPC575.

Note that the configuration of the driver 56 is not limited to theabove-described configuration exemplified in the present embodiment. Thenumber, positions, and the like of the driving magnets 532 and thedriving coils 533 provided as the driver 56 may be different from thosein the present embodiment as long as the movable unit 55 can be moved toany given position. For example, the position detecting magnets 531 maybe disposed on the top plate 511 and the Hall elements 558 may bedisposed on the movable plate 553.

Detector

The detector 57 includes the position detecting magnets 531 on the uppersurface (the surface on the top plate 511 side) of the movable plate553, the Hall elements 558 on the upper surface (the surface on the topplate 511 side) of the DMD substrate 552, and the position detecting FPC564.

Each of the position detecting magnets 531 is made of a rectangularparallelepiped permanent magnet and forms a magnetic field extending tothe DMD substrate 552 disposed between the top plate 511 and the baseplate 513.

The Hall elements 558 are disposed on the upper surface of the DMDsubstrate 552 at positions facing the position detecting magnets 531(see FIG. 8).

The Hall element 558 is an example of magnetic sensor and transmits asignal according to a change in magnetic flux density from thecorresponding position detecting magnet 531 to the drive controller 12of the system control unit 10. The drive controller 12 detects theposition of the DMD 551 based on signals transmitted from the Hallelements 558.

Similarly with the driving FPC 575, the position detecting FPC 564 isconnected to the control board 514 via a connector. One end of theposition detecting FPC 564 is moved in parallel in the plane or rotatedby the movable unit 55 and the other end is secured to the stationaryunit 51. Accordingly, the position detecting FPC 564 need to have afunction of absorbing the movement amount of the stationary unit 51without hampering the movement of the stationary unit 51. Therefore, aplurality of creases are formed in the position detecting FPC 564 so asto absorb the movement amount of the stationary unit 51 even when oneside of the position detecting FPC 564 moves with the other end of theposition detecting FPC 564 fixed.

In the present embodiment, the top plate 511 and the base plate 513formed of a magnetic material function as a yoke plate and constitute amagnetic circuit including the position detecting magnets 531. Amagnetic flux generated in the driver 56 including the driving magnets532 and the driving coils 533 disposed between the sub plate 515 and theheat sink 554 concentrates on the base plate 513 functioning as the yokeplate, thus suppressing leakage of the magnetic flux to the detector.

Accordingly, the magnetic flux generated in the driver 56 concentrateson the sub plate 515 and the heat sink 554, thus suppressing leakage ofthe magnetic flux to the outside from between the top plate 511 and thebase plate 513.

Thus, in the Hall elements 558 disposed on the DMD substrate 552, theinfluence of magnetic fields formed in the driver 56 including thedriving magnets 532 and the driving coils 533 is reduced. Therefore, theHall element 558 can output a signal corresponding to a change inmagnetic flux density of the corresponding position detecting magnet 531without being affected by the magnetic fields generated in the driver56. Thus, the drive controller 12 can grasp the position of the DMD 551with high accuracy.

The drive controller 12 (see FIG. 2) can accurately detect the positionof the DMD 551 based on the outputs of the Hall elements 558 whoseinfluence from the driver 56 is reduced. Accordingly, the drivecontroller 12 can control the magnitude and direction of the currentflowing through each of the driving coils 533 according to the detectedposition of the DMD 551, thus allowing the position of the DMD 551 to becontrolled with high accuracy.

Note that the configuration of the above-described detector is notlimited to the configuration exemplified in the present embodiment. Thenumber and positions of the position detecting magnets 531 and the Hallelements 558 as the detector may be different from the number andpositions of the present embodiment as long as the position of the DMD551 can be detected.

For example, the position detecting magnets 531 may be disposed on theupper surface of any one of the top plate 511, the intermediate plate512, the control board 514, and the movable plate 553. The Hall elements558 may be disposed on the lower surface of any one of theabove-described plates. Alternatively, the position detecting magnets531 may be disposed on the top plate 511, the intermediate plate 512,the control board 514, or the DMD substrate 552, and the Hall elements558 may be disposed on the upper surface of the sub plate 515.

Further, the sub plate 515 may be partially formed of a magneticmaterial as long as the leakage of the magnetic flux from the driver 56to the position detector can be reduced. For example, the sub plate 515may be formed by stacking a plurality of members including aflat-plate-shaped member or a sheet-shaped member formed of a magneticmaterial. If at least a part of the sub plate 515 is made of a magneticmaterial so as to function as a yoke plate and leakage of magnetic fluxfrom the driver 56 to the position detector can be prevented, the baseplate 513 may be formed of a nonmagnetic material.

The top plate 511, the intermediate plate 512, the base plate 513, theDMD substrate 552, or the movable plate 553 is preferably made of aconductive material, such as stainless steel, aluminum, or magnesiumalloy. Thus, for example, electric noise generated in the DMD 551, theDMD substrate 552, or the movable plate 553 is released to, e.g., thehousing of the illumination optical unit 40 through the top plate 511and the DMD substrate 552. Such a configuration can reduce noise leakageto the outside.

In the present embodiment, the image generation unit 50 constitutes aposition detector and a driving force generator by a combination of anytow or more of components of the stationary unit 51, the movable unit55, the driver 56, and the detector 57 constituting the image generationunit 50.

Position Detector In the present embodiment, the position detectorincludes the DMD 551, the DMD substrate 552, the position detecting FPC564, the Hall elements 558, the position detecting magnets 531, the topplate 511, the intermediate plate 512, the base plate 513, and themovable plate 553, from among the components constituting the stationaryunit 51 and the movable unit 55.

Driving Force Generator In the present embodiment, a driving forcegenerator includes the control board 514, the sub plate 515, the drivingmagnets 532, the driving coils 533, the heat sink 554, and the drivingFPC 575, from among the components constituting the stationary unit 51and the movable unit 55.

<Image Projection>

As described above, in the projector 1 according to the presentembodiment, the DMD 551 to generate a projection image is disposed inthe movable unit 55, and the position of the DMD 551 is controlled bythe drive controller 12 of the system control unit 10.

The drive controller 12 controls the position of the movable unit 55 soas to move at high speed between a plurality of positions separated by adistance less than the arrangement interval of the plurality ofmicromirrors of the DMD 551, for example, at a predetermined cyclecorresponding to a frame rate during projection of an image. At thistime, the image controller 11 transmits the image signal to the DMD 551so as to generate the projection image having been shifted according toeach position.

For example, the drive controller 12 reciprocates the DMD 551 at thepredetermined cycle between the positions separated by the distance lessthan the arrangement interval of the micromirrors of the DMD 551 in theX1-X2 direction and the Y1-Y2 direction. At this time, the imagecontroller 11 controls the DMD 551 so as to generate projection imagesshifted according to the respective positions, thus allowing theresolution of the projection images to be made approximately twice ashigh as the resolution of the DMD 551. Further, by increasing the movingposition of the DMD 551, the resolution of the projection image can bemade twice or more than the resolution of the DMD 551.

Accordingly, the drive controller 12 shifts the DMD 551 together withthe movable unit 55, and the image controller 11 generates a projectionimage corresponding to the position of the DMD 551, thus allowingprojection of an image whose resolution has been made equal to or higherthan the resolution of the DMD 551.

In the projector 1 according to the present embodiment, the drivecontroller 12 controls the DMD 551 to rotate together with the movableunit 55, thus allowing the projection image to be rotated without beingreduced. For example, in a projector in which an image generator, suchas the DMD 551, is fixed, a projection image cannot be rotated whilemaintaining the aspect ratio of the projection image, unless theprojection image is reduced. By contrast, in the projector 1 accordingto the present embodiment, since the DMD 551 can be rotated, theinclination or the like can be adjusted by rotating the projection imagewithout reducing the projection image.

As described above, the projector 1 according to the above-describedembodiment can stably increase the driving performance of the movableunit 55 in the image generation unit 50 and stably maintain the coolingperformance of the DMD 551. Accordingly, the projector 1 according tothe above-described embodiment can more stably operate and can improvethe durability.

As described above, the projector 1 according to the above-describedembodiment can shift the DMD 551 to increase the resolution of theprojection image while maintaining driving performance of the movableunit 55 and the cooling effect of the DMD 551 high. Accordingly theprojector 1 according to the above-described embodiment can have higherdriving performance, stably generate a projection image, and provide aprojection image with high reliability.

Although the image generation device and the image projection apparatusaccording to some embodiments have been described above, embodiments ofthe present invention are not limited to the above-describedembodiments, and various modifications and improvements are possiblewithin the scope of the present invention.

Numerous additional modifications and variations are possible in lightof the above teachings. It is therefore to be understood that, withinthe scope of the above teachings, the present disclosure may bepracticed otherwise than as specifically described herein. With someembodiments having thus been described, it will be obvious that the samemay be varied in many ways. Such variations are not to be regarded as adeparture from the scope of the present disclosure and appended claims,and all such modifications are intended to be included within the scopeof the present disclosure and appended claims.

What is claimed is:
 1. An image generation device comprising: an imagegenerator to receive light and generate an image; a stationary unitincluding a stationary plate; a movable unit including: a movable platemovably supported by the stationary plate, the image generator mountedon the movable plate; and a diffusion heat radiator connected to themovable plate, to cool the image generator; a driver to relatively movethe movable unit with respect to the stationary unit, the driverincluding: a driving coil disposed in the diffusion heat radiator; and adriving magnet opposed to the driving coil; and a wiring board connectedto the movable unit, to pass a current through at least the drivingcoil, wherein a movable area of the wiring board in which the wiringboard moves with movement of the movable unit does not overlap with anyof the driving coil and the driving magnet in plan view.
 2. The imagegeneration device according to claim 1, wherein an upper surface of thedriving coil and an upper surface of the wiring board are on a sameplane.
 3. The image generation device according to claim 1, wherein thediffusion heat radiator includes: a first recess disposed at a positionopposed to the driving magnet, to accommodate the driving coil; and asecond recess to accommodate the wiring board, and wherein the secondrecess is disposed at an inner side of the diffusion heat radiator thanthe first recess.
 4. The image generation device according to claim 1,further comprising: a drive controller to control the driver; and animage controller to generate an image signal according to a position ofthe movable unit and transmit the image signal to the image generator,wherein the image generator includes a digital micromirror device inwhich a plurality of micromirrors to modulate, according to the imagesignal, light emitted from a light source are arranged, and wherein thedrive controller controls the driver to move the movable unit at apredetermined cycle by a distance less than an arrangement interval ofthe plurality of micromirrors.
 5. An image projection apparatuscomprising: a light source; the image generation device according toclaim 1 to receive light from the light source and generate an image; anillumination optical unit to guide the light from the light source tothe image generation device; and a projection optical unit to projectthe image generated by the image generation device.